hot-J

I am having a stumble at WOT, mainly on the highway 3rd gear and up. What could cause this? I run 18 psi on 93, turned it down to 14, same results.
I am running Vitesse stage 3 maf/chips and turbo, no piggyback, venturi delete, S. Michi catch can, 85lb injectors, tial 46mm, new O2 sensor and the list goes on and on......

fast951

Pressure test the intake to make sure there are no vacuum leaks.

Check:
- TPS
- Ignition system (plugs, plug wires, cap, rotor, coil)

hot-J

Hey John,
plugs are new, coil is new, wires are okay, cap and rotor are fairly new, quadruple checked for intake leaks, TPS is adjusted properly, but how do I check to see if it is bad?

fast951

The DME should get the WOT signal under load.

What do you mean wires are "ok"? Bad wires will cause all sort of issues..

Do you know if it's running Rich or Lean?

hot-J

The wires are fine. I do not have a wideband to tell what its running under wot, although there isent black smoke, but at idle it is alittle rich. How would I pressure test the intake?

hot-J

I just pressurized the intake system by hooking up the air compressor to the ic pipe to the tb with the throttle open. no leaks. Sprayed soapy water on all connections. no bubbles.

fast951

Email me your name and the chip/board number if you have it. This helps me determine what you have.

hot-J

Can I find the chip board # on the chip?

blown 944

try reducing the plug gap(~.025). If that does it you need a better ignition system

hot-J

on the sticker under the chip board.... SN:000126 PN:VREPB1.0

aND THERE IS A 104 ON A SMALL CHIP ON THE TOP OF THE BOARD... whoops. -Jason Healy

hot-J

The plugs are NGK Iridium for a Mitsu EVO VIII or IX. I was told they are not suppose to be gapped, as they are pre gapped.

Rogue_Ant

Had horrible experience with Iridiums... Have tried them in a few different turbo cars, and all of them had an ignition miss/stumble.

First thing I would do is replace those with a standard set of copper plugs.

hot-J

Really? I think they work better than the BRP7ES coppers.........

fast951

Since the car was running fine. I would revisit the recent changes.. It sounds ignition related, or possibly TPS. If you can lower boost and it goes away, it's not the TPS.

Get WR6DC 1 heat range colder than stock.

hot-J

Thanks john, are those NGK?